Field of the Invention
The present invention relates to a method for imparting water repellency to the surface of a member.
Description of the Related Art
Various members may be required to have a water-repellent surface. An example of such members is a liquid ejection head included in a liquid ejecting apparatus such as an ink jet printer. The liquid ejection head is a portion of a liquid ejecting apparatus from which liquid droplets are ejected. If liquid droplets adhere to a surface of the liquid ejection head in which ejection ports are formed (hereinafter, this surface is referred to as “ejection port surface”), the adhering liquid droplets may affect the direction in which liquid droplets are ejected. In order to prevent this, the ejection port surfaces of liquid ejection heads have been made water repellent.
Japanese Patent Laid-Open No. 2010-23525 discloses a method for imparting water repellency to the ejection port surface of a liquid ejection head. In this method, a photopolymerizable water-repellent layer is formed on a photosensitive resin layer, the photopolymerizable water-repellent layer and the photosensitive resin layer are both subsequently exposed to light and developed (i.e., patterned) by photolithography simultaneously, and the resulting layers are heated to cure the layers. By this method, water repellency is imparted to the ejection port surface in the following manner: an acid is produced in the photopolymerizable water-repellent layer in response to the light emitted in the exposure step; and, when the layers are subsequently heated, water-repelling groups that include a fluorine atom are bonded in a uniform arrangement to the photopolymerizable resin layer.